That would cause chaos as we would have to adjust to the new North being the old South.
The thing to be concerned about isn't the flip itself, so much as that the fluctuations could lead to a period where the magnetic field isn't strong enough to deflect the solar wind. While it (most likely) wouldn't be permanent, it would be a pretty unpleasant period. :)
I bet the patches are not even that much needed. All software that deals with magnetic North and its relation to geographic North can deal with nothing more than a new config file telling where magnetic North is this week.
Can anyone think of any physical devices that depend on magnetic north = geographic north in a mechanical (i.e. not software) way other than a compass?
Think of all the boyscouts that will get lost without the use of a working compass! LOST I tell you!
The most obviously impactful part of the pole shift will be all the changes in migratory patterns as birds start migrating to the middle of the ocean or steppe.